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Libra? Here’s your constellation

Libra the Scales from

In skylore, Libra the Scales is an age-old symbol of divine justice, harmony and balance. Plus its two brightest stars have the coolest of all star names.

The zodiacal constellation Libra the Scales is a fixture of the evening sky during a Northern Hemisphere summer (Southern Hemisphere winter). It’s not the most flamboyant constellation of the Zodiac. But, in any year, you can find Libra fairly easily in a dark sky using two bright stars, Spica and Antares, as guides. Use these two bright stars to find two fainter stars in Libra, which, by the way, have two of the best star names in the sky. Follow the links below to learn more.

How to find the constellation Libra

Libra in history and myth

In any year, you can find the constellation Libra between the stars Antares and Spica (to the west of Zubenelgenubi, outside the chart). But in 2015, the planet Saturn acts as your guide to this fairly faint constellation. The green line depicts the ecliptic – sun’s path across the sky.

The constellation Libra the Scales and its brightest stars Zubenelgenubi and Zubeneschamali. Image via Wikimedia Commons

Obi-Wan Kenobi of Star Wars movie fame. His name rhymes with the names of the constellation Libra's two brightest stars. This image, from a poster, via Wikimedia Commons.

How to find the constellation Libra. Libra is a constellation of the Zodiac. Thus you will know to look for it along the sun’s path across our sky.

Two stars in Libra sit about midway between two bright stars, Spica and Antares. Those two Libra stars are Zubenelgenubi and Zubeneschamali, and they mark Libra’s place in the heavens.

Zuben … what? Click the links below to go to posts where you can hear pronunciations of these star names, which many have noticed sound a lot like Obi-Wan Kenobi, one of only four characters to appear in all six Star Wars films. Did George Lucas use these stars as inspiration for the character’s name? It would be interesting to know.

As seen from Earth, the sun passes in front of the constellation Libra from about October 30 until November 22 every year.

Libra’s star Zubenelgenubi sits almost exactly on the ecliptic, which is the sun’s yearly path in front of the background stars. At present, the sun has its annual conjunction with the Libra star Zubenelgenubi on or near November 7, or about midway between the September equinox and the December solstice.

However, the conjunction date of the sun and Zubenelgenubi changes over the long course of time.

Over three thousand years ago, the sun and Libra’s star Zubenelgenubi were in conjunction on the Northern Hemisphere’s autumnal equinox (Southern Hemisphere’s spring equinox). Over three thousand years into the future, the sun and Zubenelgenubi will be in conjunction on the December solstice (Northern Hemisphere’s winter solstice or Southern Hemisphere’s summer solstice).

Irrespective of which constellation provides a backdrop for the sun on the September equinox, the sun is said to be at the first point of (the sign) Libra when it the crosses the celestial equator going from north to south.

At the return of the golden age, the goddess Astraea will dispense justice and weigh the souls of men. Image credit: Wikipedia Commons

Libra in history and myth. Several thousands of years ago – around 2,000 B.C. – the ancient Babylonians apparently associated this constellation with scales or a balance. Quite possibly, this association was made because the sun on the autumn equinox shone in front of the stars of Libra at that time. It’s at the equinox that the world realizes its seasonal and temporal balance, between the extremes of heat and cold, and with day and night of equal length all over the globe. Metaphorically, Libra the Scales serves as an age-old symbol of divine justice, harmony and balance.

In contrast to their Babylonian forebears, the ancient Greeks seemed to regard Libra as the outstretched claws of the constellation Scorpius the Scorpion. In fact, the names for Libra’s two brightest stars are Arabic terms that harken back to these olden times when Scorpius reigned as a double or super constellation. Zubenelgenubi translates into “the southern claw of the Scorpion” and Zubeneschamali into “the northern claw of the Scorpion.”

The Romans, though inheriting much of the Greek tradition, again revived Libra as the only inanimate constellation of the Zodiac. In Roman thought, the constellation Virgo is the embodiment of Astraea, the Starry Goddess, holding Libra, the Scales of Justice.

Astrologers regard Libra as the second air sign, ruled over by the planet Venus. Although astronomy and astrology have been intertwined historically, they are now regarded as separate disciplines. Astrology assumes the positions of heavenly bodies have certain influences over human affairs which most modern-day astronomers regard as unfounded.

Bottom line: Libra the Scales – a constellation of the Zodiac – can be found in the evening sky during Northern Hemisphere summer (Southern Hemisphere winter). It’s situated between two bright stars, Spica and Antares. Libra’s two brightest stars are Zubenelgenubi and Zubeneschamali, whose names rhyme with Obi-Wan Kenobi of the movie Star Wars.